<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
</head>
<body>
	<details open>	 <!-- 默认情况下是关闭，可以用open -->
		<summary>前端工程师</summary>
		<p>html/css/javascript</p>
	</details>
</body>
</html>